Precision instrument



Oct. 15, 1929. J. E. RICHMOND PRECISION INSTRUMENT Filed 15, '1927 2 Sheets-Sheet FIG.

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Oct. 15, 1929. J. E. RICHMOND PRECISION INSTRUMENT Filed NO 15, 1927 2 Sheets-Sheet lflvehfor Job/7 f. Pick/1700a.

I oflffo zwey Patented Get. 15, 1929 UNITED, STATES PATENT OFFICE JOH E. RICHMOND, OE EUGENE, OREGON, ASSIGNOE, BY MESNE ASSIGNMENTS, To THE DENTISTS SUPPLY COMPANY OE NEW YORK, A CORPORATION OE NEW YORK PRECISION INSTRUMENT The present invention relates to a precision instrument for dental articulators and particularly that type known as the Gysi simplex articulator described in detail in Letters Patent No. 1,041,270, dated October 15, 1912. The purpose of this appliance is to enable the operator to place his models and bite on the Gysi simplex articulator accurately, that is to Say, with the occlusal plane of the bite coinciding with the occlusal plane of the articulatorat the time the models are being secured to the bows. 7

With the above and other objectsin View, the nature of which will be more fully understood from the description hereinafter, the invention consists in the novel construction of precision instrument, as hereinafter more fully described and defined in the claims.

Referring to the drawings: Fig. 1 is a side 2 elevation of an articulator showing myprecision instrument attached thereto; Fig. 2 is a vertical section showing the manner in which the arms of the instrument are engaged with the standards of the articulato-r; Fig. 3 is a horizontal section taken substantially on the line 3-3 of Fig. 1, looking in the direction of the arrow; and Fig. 4 is a vertical section of a fragmentary detail taken substantially on the line 1-1 of Fig. 3. U

From the drawings, it will be seen that the articulator illustrated is of conventional construction and is of the .Gysi type, as is disclosed in his patent above mentioned, except that the incisor guide pin, usually held by the sleeve 1 by means of the set screw 2, is absent. The upper model holding bow 3 and the lower model holding bow 4; are held in relation to each other by the usual frame which includes the standards 5 provided intermediate their .40 ends with projections 6 which define the occlusal plane of the articulator.

My improvements consist more particularly of a metal arch 7 at the extremities of which, on the outer surface, are depressions 8 which,

when the appliance is placed on the articulator, engage the projections 6, 6, and are supported thereby. At the center of the arch 7 and at right angles to the plane thereof, is

fixed a post 9 of such length that when the 60 appliance is positioned onthe articulator, the

be evident without a moredetailed descripprojecting pointer 10, fixed to the center of the arch on its concave side, will assume a position in the occlusal plane similar to that heretofore assumed by acorresponding projection on the incisor guide pin disclosed in said Letters Patent and forming a part of the articulator.

The terminal arms 7 a of the arch are tapped at 13 and contact screws 12, 12, fitted in such a position that when a bite and models are to be held in position they can be turned in and engaged with the wax of the bite. There may be several such tapped holes 13 on each of the arms to permit'of the screws 12 being positioned further back or forward, as preferred, to suit models ofvarying sizes. There is also a short metal pin 13 of such length that, when it is substituted and adjusted for the usual incisor guide pin and rests upon the arch 7, when in position, the. upper model holding how 3 will be held in the proper operative relation to the lower bow 1.

To operate the appliance, the arch 7 is sprung into position, engaging the projections 6, 6, on the artioulator, and the usual incisor guide pin is removed and replaced with short pin 13. The upper model bow 3 is then raised into a perpendicular position so as to allow of the introduction and temporary a tachment of the models and bite to the arch 7.

The models and bite should be securely waxed together.

The projecting pointer 10 is pressed into the wax of the bite where the medium line crosses the occlusal plane. The

.contact screws 12 are then screwed in until and while so held soft plaster is applied to securely attach them to the respective bows of the articulator and, after the plaster has set and hardened, the screws 12, 12, are loosened and the appliance arch 7 removed, leaving the models attachedto the bows. f

It is thought that the construction, operation and advantages of the invention will now tion. I have, in the present instance, shown and described the preferred embodiment of my invention which will give, in practice, satisfactory and reliable results, and it is to be understood that the same is susceptible of modification in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

Having thus described my invention, what I desire to secure by Letters Patent is:

1. A precision instrument for articulators of the character described including an arch having rearwardly arranged yielding'arms to provide a detachablespring snap engagement with the articulator frame, means for engaging the arch with the wax of a bite and means for mounting the arch in the occlusal plane of an articulator and on the lower frame of the articulator and independent of the upper frame thereof.

2. A precision instrument for articulators including an arch body having resiliency and depressions in the outer side of its terminal arms, a projection extending from the middle of the arch body on its concave side, and adjustable clamping screws threaded through the arms of the arch body, and wherein further, the width between the depressions on terminal arms of the arch body is normally greater thanthe distance between the parts of the articulator frame with which they resiliently engage.

3. A precision instrument for .articulators including an arch body of spring metal hav ing an engaging means in the outer side of its terminal arms for supporting it, a projection extending from the middle of the arch body on its concave side in the plane of the body, clamping screws threaded through the arms of the arch body, and a post secured to and eX- tending from the middle portion of the arch body at substantially right angles to its plane,

combined with the lower frame of the articulator having at its rear inwardly directed fixed projections at the level of theocclusal plane for providing a snap engagement of the arch-shaped body and also having a guide for versely through the side arms of the arch, a

post depending from the middle of the arch at substantially right angles to its plane for engagement with the incisor guide incline of I the lower model'bow of the articulator, and a pin carried by the upper model bow engaging the middle of the arch.

5. In combination, an articulator including a frame having projecting means at the 00 clusal plane thereof, and a precision instrument having an arch shaped body formed of spring metal having depressions in its extreniity for detachable engagement with said projections, a projection extending from the center of the arch body from its concave face, clamping means on the arch body for engaging the wax ofa bite, and means for supporting the arch portion of the arch body in the occlusal plane of the articulator comprising an incisor guide on the frame and a post on the underside of the middle of the arch body at substantially right angles to'the plane of said body for engagement with the incisor guide.

6. A precision instrument for articulators, including an arch body formed with rearwardly extending arms said'arms having elasticity whereby theymay'be relativelymoved toward or from each other, the rear ends of said arms provided with engaging means for detachably securing the arch to an articulator under the elasticity .of said arms and supporting it in the occlusal planeof sai d articulator, and means foricentrally positioning the waxed models in the-arch body prior to being cemented tothe bows of the articulator.

In testimonyof which invention, 1 hereunto set my hand. p 7 JOHN E. RICHMOND. 

